RB1 and cancer: Included in this category are genes whose products are not involved, according to KEGG Pathways, 2020, in critical signaling pathways in cancer, i.e., RAS–RAF–MEK–ERK, PI3K–PKB/AKT, WNT, JAK–STAT, PLCɣ–PKC–MEK–MAPK, ESR/JUP–FOS/JUN/SP1/NCOA/ESR, MYC/c-MYC–CCND–RB1–E2F, RAS–RALGDS–RHO–JNK, NOTCH–HER/ERBB2–HES/HEY–VEGFR3, HIF1–VEGF, and TGFB–TGFBR–SMAD, but this does not reduce their importance in the tumor process.